Steam engine



STEAM ENGINE Original Filed April 8, 1921 Cil Patented Nov. 29, 1927.

unan/STATES -P HERMAN Gf. MUnLLnR/or nain,"rnivtisvnvnnin, Assisnon To SKINNER ENGINE COMPANY, F ERIE, PENNSYLVANIA,

A CBPORATION 0F PENNSYLVANIA.

STEAM ENGINE.

VApplication led April S, 1921, Serial No. 459,611. `Ittenewed. February 10, 1927.

i It is desirable the operation of steam engines toprovide for compression through the action of the exhaust system. Where there is a variation in the `exhaust backpressure this variation disturbs the compression. The present invention is designed te provide means for controlling'the compression so as to avoid the disturbance due to` variations in back-pressure.

The invention is illustrated in the accompanying drawings as follows Fig. 1 shows a horizontal section of a portion of a cylinder.

Fig. 2 a side elevation of the same with the controlling mechanism in vertical section.

1 marks the power cylinder, 2 the piston operating therein, 3 the steam inlets, and 4 the exhaust ports. These may be of common construction. As shown they are arranged for a una-flow engine. Clearance varying cylinders 5 are connected by ports 6 with the ends of the cylinder 1. Pistons? are arranged in the cylinders 5 and connected t by a rod 8, the rod extending through a gland 9 in one of the cylinders. The pistons are at the same sides of the ports 6 so that the capacity of the cylinders 5 at the port ends of those cylinders are varied with movements of the pistons 7 in the same direction.

The rod 8 is connected to a piston 10 in a motor cylinder 11, glands 12 being provided in the heads of the cylinder 11 in the usual manner. The cylinder has the ports 13 extending to a valve chest 14 controlled by a valve 15. Motor fluid of any convenient type is supplied through a pipe 15a to the center of the valve 15. It will readily be seen as the valve is moved one way or the other fluidv is admitted to one or the other end of the cylinder 11 and the piston 1,0

moved so as to change the positions of `the y pistons 7.

In order to `make the motor, the movable element of which is the piston 10, responsive to variations in back-pressure I provide the following mechanism for the valve`15. A.

piston 17 is arranged inthe cylinder 16. A spring 18 opposes the movement of the piston, the spring being anchored on a bridge piece 19. A connectionl 20 leads from the cylinder 16 to the exhaust pipe 21, the exhaust pipe 21 leading from the exhaust ports 4 and being the mam exhaust from the engine. It will readily be seen that with `an n increase of back-pressure the piston 17g-is movedagainst the resistance of the spring 18 and with a reduction in this pressure the Vpiece 19. A lever is pivotally connected to the stem 22 and fulcrumed at 24 on a lever 25. The upper end of the lever 23 is connected by a link 26 with the valve 15. The lever is fulcrumed at 27 on the cylinder 1 and is connected by a link 28 with the piston rod 8.

The operation of the device is as follows With an increase of back-pressure the piston 17 is moved to the right, thus moving the valve `15 to the left. Immediately motor fluid is communicated to the left of the piston 10 and this moves the pistons 7 to the right increasing the capacity of the parts of the cylinders 5 in direct connection with the ends of the cylinder 1, thus increasing the clearance to correspond with the increase 'in back-pressure so that the compression will be thus controlled. As the pistons 7 move throughthe action of the piston 10 the lever 25 is moved with the rod 8, moving the valve 15 to a closed position.` It will readily be seen that with a given position of the piston 17 the valve 15 will bebrought to closed position only with a related position of the piston 7. Consequently the movement of the clearance in the cylinders 5 and this varies ywith the back-pressure.

What I claim as new is 1. In a steam engine, the combination of a cylinder having an exhaust system cutting ofi' the exhaust kfor compression; clearance chambers connected with the endsl of the cylinder; clearance varying pistons in the clearance chambers; a motor actuating said clearance varying pistons; and pressure devices subjected to exhaust back-pressure controlling said motor.

2.`In a steam engine, the combination of a cylinder having an exhaust system cutting olf the exhaust for compression; clearance chambers connected with the ends ofthe cylinder; clearance varying pistons in-the chamlll) bers; al motor actuating said clearance varying pistons; a valve controlling said motor; a pressure device subjected to exhaust backpressure; and a valve gear controlling said 5 valve and actuated by the pressure device and responding to movements of the clearance varying pistons whereby the clearance varying pistons are positioned with relation to the pressure device.

3. In a steam engine, the combination of apovver cylindery having an exhaust system cutting-v 'off the exhaust for compression;

clearance varying chambers connected with y the eifdsV of the cylinder; clearance varying pistons in said chambers; a. rod connecting said pistons; a motor piston on said rod; a motor cylinder in which the motor piston is arranged; a valve controlling the iluidpassing to themtor cylinder; a pressure' device connected to the back pressureg" a 'lever connected to the pressure device and the valve; and a second lever on which the first-mentioned lever stul'crurned,l said second lever being connected at one end to said rod and the other end having asta'tionary fulcrun.

In testimony whereof I have hereunto setmy hand.

HERMAN G. MUELLER.- 

